Cutting machine



Patented Dec. 17, 1935 ATENT OFFICE CUTTING MACHINE Charles H. Schurr,Cleveland, Ohio, assignor to The Lees-Bradner Company, Cleveland, Ohio,

a corporation of Ohio Application April 13, 1932, Serial No. 604,969

8 Claims.

'I'his invention relates to cutting machines and is particularlyapplicable to hobbing machines, milling machines and the like.

An object of the invention is to provide an improved machine in which aplurality of units may be compactly grouped and attended by a singleoperator.

Another object of the invention is to provide an improved machine havingfew and simple parts.

Another object is to provide an improved machine ,which will be speedyin production and simple in operation.

Another object is to provide an improved machine which will beeconomical to manufacture and operate.

Another object is to provide an improved machine in which a number ofunits may be driven from a common source of power` by simpletransmission means.

Other objects will hereinafter appear.

The invention will be better understood from the description of onepractical embodiment thereof illustrated in the accompanying drawing, inwhich:

Figure 1 is a side elevation, with parts broken away or in section, ofan assembled machine having a number of units designed for hobbinggears;

Figure 2 is an enlarged, vertical, fragmentary, sectional view taken onthe line II-II of Figure 1; and

Figure 3 is a fragmentary view showing a modified form of clutchactuating mechanism.

The apparatus shown comprises a stationary bed I upon which, and adaptedto rotate about a vertical axis, is mounted a base or table 2. Thecentral portion of the bed extends upwardly through the center of thebase, as indicated at 3, while the base has a downwardly extendingcentral flange 4 fitting within the hollow of the bed and surroundingthe projection 3.

The exterior of the bed is formed with an upturned ange 5 forming anannular trough 6 for the reception of cooling fluid and chips.

Keyed to the downwardly projecting flange 4 of the base is a worm wheel'I with which meshes a worm 8 carried by a horizontal shaft 9 journalledwithin the bed and connected by means 'of a clutch III with an electricmotor II or other driving means, so thatthe motor, through the worm andworm wheel, causes the base to rotate upon the bed.

Secured upon the upper end of the base or platform 2 are a number ofmachine units, each shown as constituting in effect a hobbing machine.Each machine unit consists of a main frame I2 having at its bottom ahorizontal flange t3 secured upon the upper surface of the base as byscrews I4. are connected to a ring I5 which serves to brace one frame tothe other.

Formed upon the frame are two pairs of vertical ways I6 and I'I, on onepair, I 6, of which is slidably mounted a carriage I8 having formeduponit horizontal ways I9, and in these horizontal ways a slide or carrier20 is arranged for translation.

Upon the carriage is journalled a horizontal shaft 2l having at one enda bevelled gear 22 15 meshing with a bevelled gear 23 splined to avertical Ashaft 24, these twe bevelled gears being housed within aprojection 25 of the carriage.

The horizontal shaft 2| is itself splined to another horizontal shaft 26journalled upon the 20 slide, and the second horizontal shaft isprovided at its end with a bevelled gear 2l meshing with a bevelled gear28. The last mentioned gear is journalled in head 29 adjustablyconnected to the slide and arranged to be adjusted angularly about 25the axes of the horizontal shaft 26, and the head carries, within ahousing-like extension 30, change gears 3l by which a spindle 32, alsojournalled in the head, may be driven from the vertical shaft at anyselected speed. Upon this 30 spindle is secured a hob or cutting tool.-

The lower end of the vertical shaft 24 is journalled with a bracket 33secured to the frame, the end projecting just beyond this bracket.Within the bracket, the shaft has keyed to it a 35 bevelled gear 34meshing with another bevelled gear 35 upon a horizontal stub shaft 36,also journalled in the bracket and provided at its other end with a spurpinion 3l which drives another spur pinion secured to the end of a hori-40 zontal shaft 38. The end of the vertical shaft is provided with oneelement 39 of a clutch, adapted to be engaged by a meshing element 40splined to the upper end of a vertical shaft 4I journalled in the baseor table. This clutch 45 element is operated by a lever 42 extending tothe outer side of the unit.

Keyed upon the lower end of shaft 4| is a pinion 43 rolling upon aninternal gear 44 keyed to a circular flange 45 formed upon the bed. 50

Obviously, a train of gears can be interposed between shafts 4I and 24,as in general it will be found more advantageous to have the lattershaft rotate at a higher speed than would be thecase if the shafts weredirectly. joined to- The upper surfaces of the frames 5 gether. However,such gears have been omitted from the drawing for the sake of clarity.

The end of the horizontal shaft 38 adjacent the pinions is journalled inthe bracket 33, while the shaft itself extends through a housing 46 inwhich it is also journalled, being provided on its outer end with achange gear 41 meshing with a second change gear 58 upon a parallelshaft 49 also journalled in this housing.

The last mentioned shaft has formed upon it, within the housing 45, askew gear and a worm 50. 'I'he worm meshes with a worm wheel 5|rotatably mounted upon a spindle 52 supported in bearings 53 within thehousing.

Keyed to the worm wheel is a gear 54 with which. mesh pinions 55constituting part of a spur differential mechanism, these pinions inturn meshing with other pinions 56 of the differential mechanism, whichlatter engage a gear 5l keyed to the spindle.

These two sets of pinions are journalled within a drum-like ring 53having on its exterior` gear teeth engaged by the conjugate teeth of agear 59 upon a vertical shaft 6e journalled in the housing. This shaftpasses downwardly to adjacent the upper surface of the base and isconnected by change gears 6I to a vertical shaft G2 passing through thebase and having at its lower enda pinion 53 meshing with the ring geart4 keyed upon the exterior of cylindrical flange 45 of the bed.

Obviously, if it is not desired to use the machine to cut helical gears,this gear train may be interrupted and the shaft 50 locked againstrotation, or the differential mechanism might be entirely omitted, theworm wheel being permanently secured to the spindle.

A hood 65 is attached to the upper end of the spindle and overlies theupper end of the housing, so that dirt, chips, and cooling uid will beex cludecl from the interior of the housing.

The spindle 52 is intended to hold an arbor, or the like, by which thework is supported, and to rotate this in proper relation to the rotationof the tool upon the spindle 32 above described.

A skew gear 56 upon shaft 49 meshes with a skew gear 61 upon atransverse shaft B8, which drives, through change gears B8, a secondtrans- Verse shaft 10. This shaft is provided with a worm 1| meshingwith a worm wheel 'l2 keyed to a cam drum 13. A groove 14 cut into thedrum actuates a rod 15, having a roller fitting within the groove,connected to the carriage to move it up and down.

' Upon the upper surface of the drum is formed a cam groove which bymeans of a lever is connected to rotate a vertical shaft 16 having atits upper end a pinion 11 meshing with a rack 18 formed on the slide forthe purposes of moving Vthe slide upon the carriage.

Preferably the carriage is fed downwardly, and a counter weight isprovided to compensate for the weight of the carriage, being connectedthereto as by cables or a chain passing from sheaves supported upon theupper portion of the frame.

The means for moving the carrier and slide are not shown in greatdetail, as these are substantially the same as those illustrated inthecopending application of Homer C.'Warner and Charles H. Schurr, SerialNo. 567,276, led October 6, 1931.

In Figure 3 an automatic arrangement for 0perating the clutch 39 and 45and a second clutch in the differential drive is illustrated. In thisfigure, lever 42 is extended inwardly as indicated at 42a and providedon its inner end with a roller 42h. The lever ls also connected to themovable element 65a of a second clutch, this element being arranged tomesh with a corresponding element h, both being interposed betweenshafts 6I and 6l which correspond to shaft 6| of the embodimentillustrated in Figure 1. Upon projection 3 of the bed is formed at onepoint a bracket 3a provided with a downwardly in clined cam surface 3bwhich engagesv and depresses the roller when the unit reaches theoperators station. By depressing the inner end of lever 42', the camdisengages the clutch elements 39 and 4e', 69a and 5th automatically,stopping all rotation of the spindles caused by the drive either frompinion 43 or from pinion 63. A spring 42o raises the inner end of thelever, when it is released from the cam 3b, causing the engagement ofboth clutches. Obviously, lever 42 could be extended and provided with ahand grip by which the operator could at any other point disengage theclutches.

The operation of the device is as follows:

rlhe gears 3l, 4l, and se are chosen so that the relative rotation ofthe work and cutter spindles are in any desired relation. Gears 59 arearranged to rotate the cams at a suitable speed. Gears 5l, if themachine is to be used to cut helical teeth, are selected to operate thedifferential mechanism at a speed related to the helix angle of the workto be produced. Y

Having adjusted all parts, the operator engages clutch ll?, so thatmotor i l causes the base to revolve upon the bed. As each unit reacheshis station, he operates the handle 42 of the unit to release its clutch(or clutches, if vtwo are used), stopping er nearly stopping therotation of the spindles. Of course, with the apparatus of Figure 3,this step is performed automatically and not by the operator.

The operator next places an arbor with a work gear secured upon it inthe spindle 52 and brings the tail stock 1.9 down so that itsdead-center 30 engages the arbor. As the unit passes the operatorsstation, the clutch or clutches Aoperated by the lever are engaged,either manually or by the cam mechanism, and, due to the motion of thetable on the bed and the rolling of pinion 43 upon internal gear 44,power is transmitted to vertical shaft 24 and thence through horizontalshafts 2! y and 2E to cutter spindle and by shafts 36, 38, and 49 to theworm driving the work spindle. The motion also is transmitted throughgears S6, 5S,

and Il to operate the cams by which the slide fed horizontally and thecarriage vertically.

As the carriage moves vertically, the rotation on the table causespinion 63 to roll upon ring gear B4, imparting an increment of rotationof spindle 52 through the differential mechanism, this incrementcorresponding to the helix angle which is to be cut upon the work gear.When the cutter has travelled the entire distance through the blank andbeen returned to its starting posi- I claim:

1. A hobbing machine comprising a bed, a frame rotatably carriedthereby, means for rotating the frame upon the bed, a spindle journalledin said frame, a carriage slidable upon said frame in a directionparallel to said spindle, a slide movable on said carriage in adirection normal to said spindle, feed means for moving said spindlesrelative each other, a spindle journalled on said slide, a common driveshaft, gearing connecting said drive shaft to said second mentionedspindle, gearing connecting said drive shaft to said first mentionedspindle including a differential mechanism, feed means operated by saidcommon drive shaft for moving said carriage upon the frame and saidslide upon the carriage, and gearing between the bed and one element ofthe differential mechanism whereby said element is operated by themovement of the frame upon the bed independently of said feed means.

2. A hobbing machine comprising a bed, a frame rotatably carriedthereby, means for rotating the frame upon the bed, a spindle journalledin said frame, a carriage slidable upon said frame in a directionparallel to said spindle, a slide movable on said carriage in adirection normal to said spindle, a spindle journalled on said slide, acommon drive shaft, gearing connecting said drive shaft to said secondmentioned spindle, gearing connecting said drive shaft to said firstmentioned spindle including a differential mechanism, and a shaftconnected to and driven by said drive shaft rotating two cams,connections between one cam and the carriage, connections between theother cam and the slide, and gearing between the bed and one element ofthe differential mechanism whereby said element is operated by themovement of the frame upon the bed.

3. A hobbing machine comprising a bed, a frame rotatably carriedthereby, angularly disposed spindles carried by the frame and movablerelative each other, a gear train connecting said spindles to rotatethem at relatively xed speeds, and including gearing actuated by therelative motion of the frame and bed to rotate one of the spindlesrelative the other, and feed means moving said spindles relative eachother and independent of the relative motion of the frame and bed.

4. A hobbing machine comprising a bed, a frame rotatably carriedthereby, angularly disposed spindles carried by the frame and movablerelative each other, a gear train connecting said spindles to rotatethem at relatively fixed speeds and including a differential mechanismactuated by the relative motion of the frame and bed to rotate one ofthe spindles relative the other, and feed means moving said spindlesrelative each other and independent of the relative motion of the frameand bed.

5. A hobbing machine comprising a bed, a frame rotatably carriedthereby, means for rotat- 10 ing the frame upon the bed, a carriagemovably carried by the frame, a Slide movable upo'n said carriage, aspindle journalled in the slide, a spindle journalled in the frame, agear train between said spindles including a differential mechanism, 15one element of each differential mechanism being rotated by movement ofthe frame on the bed, and feed means for moving said carriage.

6. A hobbing machine comprising a bed, a

frame rotatably carried thereby, means for rotat- 20 ing the frame uponthe bed, a carriage movably carried by the frame, a slide movable uponsaid carriage, a spindle journalled in the slide, a spindle journalledin the frame, a gear train between said spindles including a diierentialmechanism, one element of said differential mechanism being rotated bymovement of the frame on the bed, feed means for moving the carriage,and feed means for moving the slide upon the carriage, both of said feedmeans being driven by said gearing. 30

'7. A hobbing machine comprising a bed, a frame rotatably carriedthereby, spindles carried by the frame and movable relative each other,a gear train connecting said spindles to rotate them at relatively fixedspeeds,4 and including gearing 35 actuated by the relative motion of theframe and bed to rotate one of the spindles relative the other, and feedmeans moving said spindles relative each other and independent of therelative motion of the frame and bed. l

8. A hobbing machine comprising a bed, a frame rotatably carriedthereby, spindles carried by the frame and movable relative each other,a gear train connecting said spindles to rotate them at relatively xedspeeds and including a differ- 45 ential mechanism actuated by therelative motion of the frame and bed to rotate one of the spindlesrelative the other, and feed means moving said spindles relative eachother and independent of the relative motion of the frame and bed. 50

CHARLES H. SCHURR.

